SessionID addition, modifications

[staceygoers]

Goal: Further refine the "day" definition used within the framework's current implementation of sessionID for analytics comparisons, to allow certain analytics providers to refine their analyses, and add an additional, optional sessionID.

Proposed new definition:

One day: 12 a.m. to 12 a.m., based on the user's device time zone at 12 a.m.. If a user's device time zone changes in the middle of the day, then the client should treat this event as the beginning of a new day and generate new IDs (see below) as needed.

mediaSessionID: A GUID generated by the client for each played media file per day per client. A mediaSessionID remains constant for that media file until the next day. For example, if a user listens to five media files in one day, there will be five mediaSessionIDs. If they listen to the same media file on their phone and then on their tablet, there will be two mediaSessionIDs. If they listen to one media file twenty times in one day, there will be one mediaSessionID. Required.

sessionID: A GUID generated by the client per day per client. A sessionID remains constant for a client until the next day. For example, if a user listens to five media files in one day, there will be one sessionID. If they listen to the same media file on their phone and then on their tablet, there will be two sessionIDs. If they listen to one media file twenty times in one day, there will be one sessionID. Optional.